Hi,

My driver's electric window is starting to fail. When closing, it seems to go up ok, but when it get's to the top, it doesn't stop. It vibrates heavily until you release the button.
There is a lot of wind noise while driving, and it leaks water when I am washing the car.
I presumed this was just the sliding jaw, but a dealer has told me the window requires a new regulator.
What does the regulator do? I thought if the regulator had gone, the window would totally stop working.
I'm fed up with spending hundres of pounds at dealerships, I want to make sure I'm not being screwed.

Thanks for all your help.

P.S The trouble is on the 300se.

the window regulator is the mechanical structure that goes between the motor and the window itself.usually a conglomeration of cables gears and springs. pleanty of these components can fail without notice. i would take your door apart and see if its something simple. roll it up and down a few times so you can see how that particular one works. most commonly on benzes ive seen these nylon siding
fittings on the base of the window crack in half which causes the problem you described. whole window regulators are inexpensive and easy to replace. i paid about $120 dollars for one a few months ago for my 300E. it included a motor also. hope this helps!
good luck,
adam